Blog posts tagged with 'huffman':



Deflating the universe

Date: 02 Jun 2010
Tags: [ compression ]  [ deflate ]  [ gzip ]  [ huffman

Compression is used all around us every single day. You (or your girlfriend/wife most likely) folds your clothes nicely so they all fit in your closet. When recycling, you flatten the cardboard milkboxes so they take up less space and you probably even text your friends with messages like: “hi, how r u? w r u? cya, xxx”. Stuff like that.

In the computer world, compression probably plays even a more important factor. When compressing data, it take less space and thus less time to send it over to somebody else through internet. Years ago, you bought a 100MB harddrive and use special software to increase the capacity to (up to) 200MB (doublespace, stackspace for those who can remember). It all uses compression one way or the other.

Some compression methods can compress and decompress in such a way that the decoded output is exactly the same as the original. For instance, gzip and deflate. It’s called lossless compression since no data is lost during the compression/decompression. Other compression methods don’t. For instance, JPEG or MP3 compression creates smaller copies of the original but they can never be decompressed back to the original format. Colors that are very similar (but not quite the same) are converted into 1 single color during JPEG compression. Or inaudible sounds are removed from an audio file when compressing to an MP3. With JPEG or MP3’s, for most people this is not an issue. The images are perfect enough for normal usage, and the audio quality of mp3’s are also good enough for the average use (although I know a few persons who want to kill me for saying this :)).

In this article I will talk a bit about the deflate compression method. A compression method used throughout the whole internet and probably the most used compression algorithm today.

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